Storage system for and method of storing and removing from storage alpha liquid



`April 26, 1927. 15,626,066

M. B ANFENGER STORAGE SYSTEM FOR AND METHOD OF STORING AND REMOVING FROM STORAGE A LIQUID Filed May 13. 1925 sroseen svs'rnn son im METHOD mirent* oFFicE.

OF STORINGAND REMOVIN G FROM STORAGE A Application. med my 1s, 1925. serial No. 30,076.

This invention relates to storage systems of the type employed, for example, in the storage of petroleum and other oils, and 1t also relates to methods of storing and ref moving from storage a liquid, and an object of the invention, in general, is to minimize the hazard always present in the storage of oil.

More particularly an object is to provide for the storage of volatile petroleum products or other volatile liquids, in a manner that they will 'be completely removed from any contact or communication with the atmosphere.

Another object is to reduce the vapor or gas space in the container or tank to a negligible amount.

Another object is to edect the storage ot volatile liquids upon a body ci water and edect automatic control of thev volume of water in accordance with the volume of 'the volatile liquids. h

mother object is to make it possible to employ i'ioating roof for the container or tank that is absolutely gas tight,

A still further object is to accomplish the foregoing without it being necessary to make radical departures trom conventional design of the container and without lthe development of such pressure or partlal vacuum in the container as would make it necessary to provide a relatively heavy construction.

The conventional type ci? storage tank, when partially illed with liquid, contalns *l and, second, because of the possibility of the inrlammable stream of air and gas,that emerges from the tank becoming accidentally ignited, thus setting fire to the entire contents oi' the tank.

Even when a conventional storage tank for petroleum products is standing idle, the gas above the liquid expands and contracts as its temperature changes during the day.

E. ANFENGER, @E SAN FBANGISCO, CALIFORNIA, ASSIGNOR, BY MESNE i ASIGNMEIQTS, T@ STANDARD OUA COMPANY OF CALIFORNIA, OF

SAN FRANCISCO,

LLIFOBNI, CORPORTION 0F DELAWARE, 4

and, consequentl since it is impracticable to construct tan ys strong' enough to resist the resulting pressure, it is necessary to provide a vent to permit of the discharge of gas when the temperature rises and to permit of the influx of air when the temperature l falls. Under such conditions, there is a continual loss of the valuable vapor and there is more likelihood of an explosion taking place than would be the case if the influx of air did not take place.

Attempts have been heretofore made to Veliminate the gas or vapor space above the liquid 1n the storage tanks by two generalsystems. 'By the first, a iloating roof 1s used. The floating roof eliminates the gas space' by riding up and down on the liquid surface as the tank is filled or emptied or as the level thereof changes because of contraction and expansion of the liquid due to changes of the temperature thereof. In the prac# tical application of such system, however, it isfound almost impossible to maintain a vapor tight seal between the floating roof and the shell of the container and a certain amount of vapor escapes around the edge of the roof. This vapor constitutes a fire hazard and, besides, it is of value. By'the second system, the storage tank with permanent roof is kept full of liquid at all times by substituting a volume of water equivalent to the volume of petroleumor other valuable liquid drawn off and by discharging the water as the tank is being filled with the volatile substance. This second system is readily applicable when usin small containers, butin the case of relative y large storageA reservoirs, it becomes very expensive .be- .v cause of the great strengthl of construction of the roof, necessary to resist the pressure and partial vacuum that are developed within the reservoir.

As liquids, in so far as they are used in a storage system, are substantially incompressible in such systems, it is necessary in the second system mentioned above, that the change in the volume of water at all times exact oil or other volatile liquid. The pressure of y equal the change in the volume of the water cannot be used to d1splace the volatile substance, nor can the pressure of the Water for, on account ofthe diierences in densities, the roof of the container `would be subjected to such pressure that it would have to be made iinpracticably heavy and expensive. Any mechanical synchronizing means installed to control the volume olf water would have to function with the greatest delicacy2 and the'lailure of such means to so function, even or a moment, would result in the destruction oi the roof of the reservoir.

rihe present invention aims to avoid the foregoing described diiculties.

The accompanying drawings illustrate the invention:

Figl is a sectional elevation oi a storage 'system embodying the invention, the view beingmore or less diagrammatic.

Fi 2 'is an enlarged sectional fragmental detai to illustrate the liquid seal and the roof drain.

Referring to the drawings, there is provided a storage tank 3, a water reservoirV 4l, and an elevated stand pipe 5. The stand pipe 5 supplies Water through a pipe 6 to .the tank 3 and the ilow'of Water to the tank is controlled by a valve 7 on the pipe 6. Water discharges from the tank 3 to a pipe 8 into the reservoir d, there being a valve 9 on the pipe 8 to control the outflow oa Water from the tank.

Water is fed from the reservoir el to the I stand pipe 5 through a pipe line 10, there being a pump 11 in said pipe line to litt the water. This pump 11 may be operated by an electric motor 12 to which electric current is supplied through an electric switch 13 that is operated by an arm 1d provided With a doet 15 that rests in the body of Water in the stand pipe. Dropping of the arm le to a lower predetermined level closes the switch so as to pump Water from the reservoir into the stand pipe and, when the Water in the stand pipe reaches a predetermined higher level, the switch is opened by raisingl of the arm 14.-.

The tank, 3 has a loating roof 16 which is provided with a dange 17 that dips into a liquid seal 18 surrounding the rim .of the tank. Downvvard movement ot the roof 16 is preferably limited by a system' of posts 19 inside ot the tanln These posts 19 support the roof, in event of the liquid below a' predetermined level, as caused by failure of the water su .u 6 or drain pipe 8 to properly function. The tank 3 with its floating roof yieldingly con fines the liquid al, that is to be stored also the liquidb that is employed seal.y

beneath the liquid a to further seal the liquid a from the atmosphere.

Upward movement of tbe roof 16 may be limited by providing en overflow pipe 2O which is connected to the tank at the top :tenaces thereof so as to conduct oil away'from the tank when said oil rises above a predeterflexible section 23 adjacent to the roof so as tolbe adjustable 'to the roof as it rises and fa ls.

lt is to be understood that the valves 7 9 may be manually operated, if desired, but their operation is preferably automatic by reason of the provision of linkages 24, 25 connected with the valves 7, 9, respectively. The linkage 24 is adapted to be operated by the roof 16 to open the valve 7 whenpsaid roof falls to a predetermined level andtgpperated to close the valve 7. when said roof rises to a predetermined level, and the linkage 25 is adapted to be operated by the roof to open the valve 9 when said roof falls to a predetermined level and operated to close the valve 9 when said roof rises to a pra.

determined level. lt is understood that any other suitable form of automaticxsggntrol for the valves, operated by the rise and fall of the roof 16, may be provided'in lieu of the linkages described.

ln the operation of the system described above for performing the new method, when oil is pumped into the tank 3 through the pipe 20, the floating1 roof rises and upon reaching a predetermined level elects opening of the water drain valve 9 allowing the water to discharge from the tank into the reservoir e. The drain line 8 and valve 9 are constructed to discharge Water at. a somewhat faster rate than that at which oil enters the tank. As soon as the drain valve 9 opens, the roof starts tofall, continuing downward to a predetermined level at which the drain valve is closed by operation of the linkage 25. 'When oil is pumped out of the tank, the roof falls and upon reaching a through the pipe 20, thus causing the roof to rise a distance that can be determinedby the adjustment o the linkage 24. When the root rises to a predetermined level, the linkage 24C closes the valve 7.

lin event of the level of the liquida falling to the upper ends of the posts 19, owing to improper functioning of the water'drain isa . or water supply,'the tank will not be injured as the roof will then be supported by theA posts. If the liquid a should accidentally reachla still lower level so`that there would be a tendency to create a partial vacuum beneath the roof, the vacuum breaker 21 admits air to the tank and 'thus prevents the roof, from being collapsed by a partial vacuum. A l

' From the foregoing, it will be' readily seen that in this system a perfect liquid seal is maintained for the floating roof at all times, and it will be readily understood that it is unnecessary to exactly synchronize the movement of the oil and water, since the rise and fall of the floating roof compensate for any momentary inequalities' in the flow of oil and water thus preventing the generation of pressure or partial vacuum within the tank.

f valved water drain means connected with i, the lower portion of the tank, means operated'by raising of the roof to a predetermined level to open the water drain valve and operated .by falling of the roof to a predetermined level to close the water drain valve, and means operated by falling of the roof toa'predetermined .level to open the water supply valve and operated b raising of the roof to a predetermined leve to close the water supply valve.

2., A storage systemfor liquids comprising a tank having a floating roof, a pipe comlmunicating with the up er portion of the tank, valved water supp y means connected@ 4 with the lower ortion of the tank, means operable by'falling of the roof to 'o en the valve and operable by raising of .the roof to close the valve, valved water drain means connected with the lower portion of the tank and means operable byl raising of the roofto open the drain valve and operable by falling of'the roof to close the-'drain valve.

3. A storage system for liquids vcomprising a tank hav-ing a sealed loatmg roof, a pipe communicating with theupper portion of the tank, valved water supply means connected 'with the lower portion of the tank,

means o erable by falling ofthe roof to open said v ve means and operable by raising of the roof to close said valve means, valved water drain means connected with the lower portion of the tank, and means operable by raising of the rootl to open said drain 'means and operable by falling of the roof to close said drain means.

4. A storage system for liquids comprising a tank having a sealed floatmg roof, a pipe communicating with the upper portion of the tank, a water standpipe, a valved pipe line connectingl the standpipe with the lower portion of the tank, means operable by falling of the roof to open the valve and operabe byraising of the roof to close said valve, a reservoir, a valved drain pipe connected with the lower ortion of the .tank and discharging into t e reservoir, means operable by raising of the roof to open the drain valve and operable by falling of the roof to close said drain valve, a pipe line leading from the reservoir to the standpipe,

a pump in the last named (pipe line, a motor to operate the pump, an means whereby `lowermg of the water in the standpipe to a predetermined level effects operation of the motor.

Signed at San Francisco, Calif., this 4th day of May 1925.

- MAXIMILIAN B. ANFENGER. 

